Expanding collar



Nov. 29, 1938. i E. T. STRAUBEL EXPANDING COLLAR Filed Aug. 5, 1937 Patented Nov. 29, 1938 UNITED STATES PATENT OFFICE EXPANDING COLLAR Ernest 'l. Straubel, Green Bay, Wis.

Application August 5,

3 Claims.

The invention relates to an expansion collar for mounting on shafts and more particularly it relates to a collar adapted to be associated with the end of a tubular core and to operatively en- .5 gage the core with the shaft whereby a sheet of paper or other material may be wound about the core to form a roll and the paper be'unwound from the roll by the resulting rotation of the core with the shaft.

The cores are used as a nucleus for winding sheets of paper in compact so-called parent rolls, and in order that the roll may be rigid and adapted for control in unwinding of the paper from the parent rolls, such cores are usually constructed of stiff paper or cardboard stock. In order that the cores may be rigid and adapted for repeated use as nuclei for paper rolls, they are necessarily of substantial thickness and in general are of a composition such that they are relatively expensive. In order that such cores may be rotated with a shaft serving as a spindle extending through the core, it is customary to provide an expansion collar adapted to frictionally engage the shaft with an end of the core. Economy of production makes it desirable that the cores be used again and again in the winding of parent rolls, and this, in turn, requires that the collar, operatively connecting the shaft with the core, be so constructed that the core is not mutilated, or otherwise rendered unfit for repeated use.

It is an object of the invention to provide an improved expansion collar of the kind described adapted to quickly connect and disconnect'tubular cores with a shaft serving as a spindle in a manner such that the core is not mutilated, and whereby the core is rotated with the shaft to wind sheets of paper into compact rolls about the coreas a nucleus and to unwind the sheets as desired.

Another object of the invention is the provision of improvements in collars of the kind described whereby a shaft may be accurately centered in the collar and core, and the collar frictionally engage the core and the shaft at a plurality of constricted areas, whereby all possibility of the slipping of the collar relative to the shaft or the core is eliminated.

vA further object of the invention is to provide a collar of the kind described which is durable, simple, easily assembled, inexpensive to manufacture, and satisfactory for its intended purpose. 1

Many other objects of the construction herein shown and described will be obvious to those 1937, Serial No. 157,550

skilled in the art from the disclosure herein given.

To this end, my invention consists in the novel construction, arrangement and combination of parts herein shown and described, and more particularly pointed out in the claims.

In the drawing'wherein like reference characters indicate like or corresponding parts:

Fig. l is an elevational view of a shaft equipped. with two collars embodying the principles of the invention, and respectively positioned in operatlve engagement with the opposite ends of a tubular core of cardboard, the core and one of the collars being shown in longitudinal section;

Fig. 2 is a plan view of one of the collars shown in Fig. 1; and

Fig. 3 is a view drawn to a larger scale along the line 3-3 of Fig. 2.

Referring now more particularly to the drawing, the collars embodying the principles of the invention are designated by the numeral Ill, and are shown as mounted in longitudinally spaced relation on a rotatable shaft II. The shaft I l is operatively connected with any suitable driving element and is journalled in bearings not shown. The drawing illustrates the shaft II as equipped with a pair of the collars I0 adapted to operatively engage the opposite ends of the tubular core I2 of cardboard or similar material. However, in practice, a single collar I 0 is frequently used and a collar permanently fastened to or integrally formed with the shaft is used as a substitute for the second collar Ill. The shaft II is of smaller diameter than the inner diameter of the core I2, and serves as a spindle for rotating the core to wind a sheet of paper on the core to form a roll. Illustration of the sheet of paper to be wound about the core I2 is omitted as not being necessary to an understanding of the invention.

Each collar I0 consists of a member I3 and a member I4 extending longitudinally of the shaft II. The members I3 and I4 are mounted on opposite sides of the shaft I I and are pivotally connected by a pin I5. The members I3 and I4 are preferably formed by casting from any suitable metal and have their adjacent faces respectively provided with registering substantially semi-cylindrical shaped recesses I6 and I! through which the shaft I I extends as shown. The radius of curvature of the recesses I6 and I1 is somewhat larger than the radius of the shaft II to permit accurate centering of the shaft and relative tilting of the members I3 and I4 about the pin I5, as hereinafter described.

The outer end of the member I4 is substantially rectangular in cross section and has a pair of laterally spaced projections I8 bounding a recess I9. The outer end of the member I3 comprises a generally rectangular element 20 positioned in and loosely fitting the recess I9 provided by the member I4. The pin I5 extends laterally through the projections I8 and the element 20, the pin preferably having a close fit with the projections and a loose fit in a bore 2| provided by the element.

The outside peripheries of the members I3 and I4 are substantially semi-cylindrical in shape except at their outer ends. The radius of curva ture of the outside peripheries of the semi-cylindrical portions of the members I3 and I4 at their inner ends is slightly less than the inside radius of the core I2. The small diametered inner end portions of the members I3 and I4'formjaws or clamps 22 and 23, respectively, adapted to be in serted in and frictionally engage the opposite sides of the core "I21. The members I3 and I4 have a larger outside radius adjacent their rectangular portions than the radius of the jaws or clamps 22 and 23,a'nd"thereby provide shoulders 24 adapted to engage the adjacent end of the core I2. i"

The members 22 and 23 'areclamped in operative engag'ement'with the shaft II by means of a setscrew-ZE 'extendingthrough the member I3 nearitsouter end. The screw 25 has an angular recess 26 adapted to receive a correspondingly shaped key 21. whereby the screw is threaded inwardly and outwardly to vary the spacing and to tilt the members "I3 and I4, .as hereinafter more particularly described, the tilting movement being facilitated by bevelling the edges of the element 20 adjacent the recess I6 as best shown in dotted linesin'Fig. 1;

Accurate alignment of the member I4 on the shaft II is obtained by providing the opposite ends of the -member 'I4 each with a pair of 'short arcuate projections '28. The'projections 28 have their inner faces curved to conform to the curvatureand accurately? fit the shaft I I. The projections 28 are preferably formed integral with the member "I4,.an'd accurate curvature thereof is obtained by machining or by any other process suitable for'the purpose;

The described movement of the screw 25 inwardlyicenters the member I4 relative to the shaftjl I, by causing the shaft. to closely fit the arcuate projections 28 andalso moves the member 'I3 away from the member I4 until the pivot I5. :engages the inner edge of the bore 2I, as shown'in Fig. 1. The pivot I5 and bore 2I are sopositioned that'the jaws 22 and 23 are parallel and equally spaced from the axis of the shaft II when the pivot is'in the position shown. The outer semi-cylindrical surfaces of the jaws or clamps 22' and 23, respectively, fit and frictionally engage the innerperipheryof a standard core I2 throughout theirslength when the pivot is in the'po'sitionshown. Inasmuch .a'sa large number "of'core's I2 are successively and repeatedly mounted on the shaft II, it may happen that the innr'uiameters' 'o'f'fsom of the cores may vary slightly mam the standard. If such core diameter' is slightlyin' excess of the standard diameter, thej'aw 2 2 will'betilted slightly about the'pivdt I 5 1to provide the' necessary frictional engagement withfthecoreiI2; If the core diameter is slightlyless"than'thestandard, the jaws 22 and 23 wilfuniformly engage the core before the pivot I5 comes torest on tl' efinner edge of thebore 2I, in which case the screw 25"will"b'e threaded to bring the pivot to the position shown with the result that the core will be very slightly distorted throughout the length of the jaw. The substantially uniform bearing of the jaws 22 and 23 prevent any mutilation of the core and all possibility of slipping of the collar ID on the shaft I I is eliminated by reason of the five-point frictional contact provided by the screw 25 and the four arcuate projections 28.

The described relative tilting movement of the members I3 and I4 about the pin, I5 adapts the collar [0 to be quickly mounted on the shaft II and to be moved longitudinally thereof into operative engagement with the end of the core. The provision of the arcuate projections 28 enable the collar and the core to be accurately centered relative to the shaft. The simplicity of cons'truction of the members comprising the collar and the adaptability of the collar for frictional engagement with the core without mutilation thereof whereby the core may be used repeatedly 'areiimportant features'of the invention.

While the invention has been, described as adapted for use with cores forming nuclei for paperrollsand the =1ike, it is obviously adapted forja variety ofjotheriuses wherein it is desirable to-;connect -the tubular iCOre Witha shaft forming a spindle.

Thus, it will be seen that I have provided an expansion collar of novel and simple construction adapting it for exactly centering tubular members relative to 'a driving shaft-and for frictionally engaging. said tubular members with the shzifti i.alanner such that mutilation of the members. and possibility of slipping of the collar relative to the shaft or to the tubular memhers is eliminated.

Having thus described my invention, it is obvious that .various immaterial modifications may 'be made in the samewithout departing from the said sections, the outer ends 'of'said sections having contiguous overlapping portions, a pivot extending through said overlapping portions'transverselyto the axisof the shaft, and meansinitially-operableto rotate the sections relative to each other about said pivot as an axis and there'- by to engage the full length of the inserted :portio'ns ofsaid sections with the core, said means being subsequently/operable to'move said sections apart and thereby to clamp the sections in frictional'engagem'ent with the'core and to clamp saidl arcuate. portions in. frictional engagement with :the shaft.

2. A device for connecting a hollow'coreto an axial shaft, said. device comprising an elongated collar adapted to slip overtheshaft 'and consisting of two cooperating longitudinally-extending sections having contiguous inner end portions of approximately semi-cylindrical shape adapted wrangle-intimate core, the cuter end portion of on'e 'of said sebtibnsproviding a recess in which an adjacent portion of the other of said sections is positioned, a pivot transverse to the shaft extending through and connecting said outer end portions of the sections, a set screw mounted in one of said sections between the pivot and the core, an arcuate projection on the inner periphery adjacent each end of the other of said sections adapted to closely fit the shaft, said screw when threaded inwardly to engage said shaft being adapted to clamp the semi-cylindrical end of each section in frictional contact with the core and also to clamp said arcuate projections in frictional contact with the shaft.

3. A device for connecting a hollow core to an axial shaft, said device comprising an elongated collar adapted to slip over the shaft and consisting of two cooperating longitudinally extending sections having contiguous inner end portions of approximately semi-cylindrical shape adapted for insertion in the core, the outer end portion of one of said sections providing a recess in which an adjacent portion of the other of said sections is positioned, a pivot transverse to the shaft extending through and connecting said outer end portions of the sections, the pivot having a close fit with one of said sections and the other of said sections providing an aperture in Which the pivot is movable laterally toward and away from the shaft, a pair of arcuate projections adjacent each end of the inner periph ery of one of said sections adapted to closely fit said shaft, and a set screw extending through the other of said sections adapted to engage the shaft at a point intermediate the pivot and the core, said screw being operable to spread the sections apart and then to relatively rotate the sections and thereby to friotionally engage said inserted ends of the sections with the core and to frictionally engage said arcuate projections with the shaft.

ERNEST T. STRAUBEL. 

